GOALI/Collaborative Research: Autonomous Thermomechanical Fabrication of 3D Structures using Heat-Responsive Polymers

GOALI/合作研究：使用热响应聚合物自主热机械制造 3D 结构

• 批准号: 1635966
• 负责人: M Ravi Shankar
• 金额: $ 17.5万
• 依托单位: University of Pittsburgh
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2020-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1635966&HistoricalAwards=false
• 关键词: GOALI; Collaborative; Research; Autonomous; Thermomechanical

Autonomously fabricating macro-scale polymeric objects by subjecting a preform to a non-contact stimulus such as heat holds significant technological implications. For instance, it offers the ability to transform a preform (fabricated in simple, compact geometries) into target shapes on demand. It also offers the ability to simultaneously transform a large number of parts into target shapes by triggering them en masse using a globally applied stimulus. Hence, mass manufacturability emerges without an additional overhead. This Grant Opportunity for Academic Liaison with Industry (GOALI) award supports fundamental research on the self-assembly of 3D structures based on designs embedded at the molecular level in heat-responsive polymers. Research results can help spawn new technologies in applications such as biomedicine, where implants can be deployed into desired shapes and reshaped as-needed using an external stimulus.The first research objective is to establish the relationship between the spatiotemporal evolution of strain fields (leading to the creation of 3D helical structures) and controllable parameters (nematic director orientation and temperature). To achieve this objective, crosslinked, acrylate-based liquid crystalline polymers in twisted nematic configurations will be synthesized. Freely suspended polymer samples will be subjected to heat treatment with varying nematic director orientation (ranging from 0 to 45° with respect to the mid-plane of samples) and temperature (ranging from the glass transition temperature to close to the thermal decomposition temperature). The evolution of strain fields in these samples will be measured in situ using image analysis based characterization. The second research objective is to establish the effect of the displacement (preimposed on the sample) on the spatiotemporal evolution of torsional, bending strain fields (underpinning the creation of 3D prismatic and hierarchically supercoiled shapes). Various displacements (up to 20 percent of the length of the samples) will be imposed to samples. Spatiotemporal evolution of torsional, bending strain fields will be measured using imaging analysis based characterization.

通过对非接触式刺激（例如热量）进行预成型，可以自主制造宏观尺度聚合物对象具有显着的技术意义。例如，它具有按需将预成型（以简单，紧凑的几何形状制造）转换为目标形状的能力。它还提供了通过使用全球施加的刺激来触发大量触发的能力，可以轻松地将大量零件转换为目标形状。因此，质量的生产性出现而没有额外的开销。这项与行业联络的赠款机会（Goari）奖基于嵌入在热响应性聚合物中的分子水平的设计基础上，支持对3D结构的自组装的基础研究。研究结果可以帮助生成新技术（例如生物医学），在这种应用中，可以将其部署到所需的形状中并使用外部刺激进行重塑。第一个研究目的是建立应变场的空间时间演化之间的关系（导致3D螺旋结构的创建）和控制参数（导致3D螺旋结构的创建）和受控参数（NEM PAMITATEDIANTATION和DEMATITATION和DEMATITATION和DEMATITATION和DEMATITATY and DEMATITATY和DEMATITATY和DEMATITATY and DEMATITATY和DEMATITATY和DEMATIOTATION和DEMATIONTAINTIAD和DEMATEDATY and DEMATIOTINT和温度）。为了实现这一目标，将合成扭曲的列构构中的相互交联的，基于丙烯酸的液晶聚合物。自由悬浮的聚合物样品将通过不同的nematory导向进行热处理（相对于样品中间平面的范围从0到45°）和温度（从玻璃过渡温度到接近热分解温度的范围）。这些样品中应变场的演变将使用基于图像分析的表征进行原位测量。第二个研究目标是确定位移（预先在样品上）对扭转，弯曲应变场的空间时间演变的影响（基于创建3D棱柱形和层次超螺旋形状的基础）。样品将施加各种位移（最多20％的样品长度）。扭转，弯曲应变场的时空演化将使用基于成像分析的表征测量。

项目成果

Complexity from simplicity: Confinement directs morphogenesis and motility in nematic polymers

• DOI: 10.1016/j.eml.2021.101362
• 发表时间: 2021-08
• 期刊: Extreme Mechanics Letters
• 影响因子: 4.7
• 作者: A. Clement;M. Babaei;J. Phadikar;Da‐Wei Lee;A. Skandani;M. Shankar

Visco-plastic self-consistent modeling of crystallographic texture evolution related to slip systems activated during machining Ti-6AL-4V

与加工 Ti-6AL-4V 期间激活的滑移系统相关的晶体织构演化的粘塑性自洽建模

• DOI: 10.1016/j.jallcom.2020.157336
• 发表时间: 2021
• 期刊: Journal of Alloys and Compounds
• 影响因子: 6.2
• 作者: Wang, Qingqing;Shankar, Ravi M.;Liu, Zhanqiang
• 通讯作者: Liu, Zhanqiang

Effect of microstructural anisotropy on severe plastic deformation during material removal at micrometer length-scales

微米长度尺度材料去除过程中微观结构各向异性对严重塑性变形的影响

• DOI: 10.1016/j.matdes.2020.108874
• 发表时间: 2020
• 期刊: Materials & Design
• 影响因子: 8.4
• 作者: Gong, Shan;Shankar, M. Ravi
• 通讯作者: Shankar, M. Ravi

Mapping dislocation densities resulting from severe plastic deformation using large strain machining

• DOI: 10.1557/jmr.2018.264
• 发表时间: 2018-08
• 期刊: Journal of Materials Research
• 影响因子: 2.7
• 作者: Sepideh Abolghasem;S. Basu;S. Shekhar;M. Ravi Shankar

Tuned photomechanical switching of laterally constrained arches

横向约束拱门的调谐光机械切换

• DOI: 10.1088/1361-665x/ab1ce4
• 发表时间: 2019
• 期刊: Smart Materials and Structures
• 影响因子: 4.1
• 作者: Smith, M L;Gao, J;Skandani, A A;Deering, N;Wang, D H;Sicard, A A;Plaver, M;Tan, L-S;White, T J;Shankar, M R
• 通讯作者: Shankar, M R